MITRAL VALVE REPLACEMENT WITH AND WITHOUT CHORDAL EXCISION

本临床试验的目的是检验二尖瓣 瓣膜装置（瓣叶、腱索和乳头肌），如有 完整的瓣膜置换时，将防止近均匀 再灌注后左心室扩张和低心输出量相关 二尖瓣关闭不全的长期手术治疗。 具体目的是：（1）测量左室血流动力学和尺寸， 手术室中心肺转流术前后的超声检查：2）更换 单纯二尖瓣返流患者的二尖瓣， 不切除整个二尖瓣装置;（3）确定 各组术后即刻血流动力学特征;（4） 分析6个月和3年的运动能力、LV 尺寸和血液动力学标准。 这项调查的理由是希望，如果立即 长期接受二尖瓣置换术患者的转流后病程 直立性二尖瓣关闭不全可以通过防止 左心室扩张通过维持先天的物理结构， 可以降低左心、手术死亡率和支持措施， 长期的好处可能会增加。 5名患者的结果非常好。 两名患者 3例患者使用了St. Jude假体。 配对 在同一时间段内进行二尖瓣置换术的患者 术后左室功能不全的细微变化 间隔出现典型和不同于实验组。 六个月的数据很快就会出来。

The purpose of this clincal trial is to test the hypothesis that the mitral valve apparatus (leaflet, chordae tendineae and papillary muscles), if left intact at the time of valve replacement, will prevent the nearly uniform postreperfusion left ventricular dilation and low cardiac output associated with surgical treatment of mitral insufficiency of long duration. The specific aims are: (1) measure LV hemodynamics and dimensions with ultrasound prior to and after cardiopulmonary bypass in the OR: 2) replace the mitral valve in patients with pure mitral regurgitation with and without resection of the entire mitral valve apparatus; (3) determine immediate postoperative hemodynamic characteristics of each group; (4) analyze 6 month and 3 year results in terms of exercise capacity, LV dimensions, and hemodynamic criteria. The rationale of this investigation is the hope that if the immediate postbypass course of patients receiving mitral valve replacement for long standing mitral insufficiency can be altered by the mechanism of preventing left ventricular dilation by maintaining the innate physical structures of the left heart, operative mortality and support measures may be reduced and long-term benefits may accrue. The results in five patients have been excellent. Two patients have had bioprostheses and 3 patients have had St. Jude prostheses. Matched paired patients having mitral valve replacement during the same interval have had subtle changes of left ventricular dysfunction in the postoperative interval which appear typical and different than the experimental group. Six month data will be obtained soon.